_constructor = constructor;
Function.prototype.constructor = function (a) {
    if (a === "debugger") {
        // console.log(a);
        return null;
    }
    return _constructor(s);
}

// 方法2
Function.prototype.__constructor_back = Function.prototype.constructor;
Function.prototype.constructor = function () {
    if (arguments && typeof arguments[0] === 'string') {
        if ("debugger" === arguments[0]) {
            return
        }
    }
    return Function.prototype.__constructor_back.apply(this, arguments);
}

// 方法3
Function.prototype.constructor = function () {
}

var _constructor = constructor;
Function.prototype.constructor = function(s){
    if (s == 'debugger'){
        console.log(s);
        return null;
    }
    // return _constructor.apply(this, arguments);
    return _constructor(s);
}